Heat radiator for electron discharge devices



April 4, 1950 R. A. COLE 2,502,429

HEAT RADIATOR FOR ELECTRON DISCHARGE DEVICES I Filed Aug. 7, 1947 s Shets-Sheet 1- [nuentor I Alter/my April 1950 R. A. COLE 2,502,429

HEAT RADIATOR FOR ELECTRON DISCHARGE DEVICES Filed Aug. 7, 1947 3 Sheets-Sheet 2 April 4; 1950 A.IL. COLE 2,502,429

' HEAT RADIATOR FOR ELECTRON DISCHARGE DEVICES- Filed Aug. 7, 1947 3 Sheets-Sheet 3 FIG-4 A ltorney v Patented Apr. 4, 1950 HEAT RADIATOR FOR ELECTRON I DISCHARGE DEVICES Reginald Alexander Lister Cole, London, England, assignor to International Standard Electric Corporation, New York, N. Y., a corporation of 1 Delaware Application August 7, 1947, Serial No. 767,259 InGreat Britain August 22, 1939 Section 1, Public Law 690, August 8, 1946 Patent expires August 22, 1959 '3 Claims. (01. 250-275) This invention relates to heat radiators for the dissipation into a surrounding medium such as air of heat generated in electrical apparatus 'such, as electron discharge apparatus. It also relates to electron discharge apparatus incorporating heat radiators. The term radiator is used in its vulgar sense, the heat dissipation being due primarily to thermal contact with the surrounding medium.

The heat radiator of the invention comprises a plurality of separate fins adapted to interlock with the body of the electrical apparatus to be cooled.

In one form of the invention a heat radiating structure comprises a plurality of separate fins disposed radially about a cylindical shell of electrical apparatus from which heat is to be dissipated, a ring surrounding and engaging the fins at one end thereof, said ring being preferably internally slotted to space said fins and a clamping member at the other end comprising a second ring adapted to be forced axially over the fins, the fins having radially tapered portions and/or the second ring having a coned inner surface so that the fins can be urged into close contact with the shell.

The structure may form part of an electron discharge device the anode of which forms part of the envelope and constitutes the shell of the heat radiating structure.

Such an arrangement is illustrated by way of example in the accompanying drawings of which:

Fig. 1 is a side view of the complete electron discharge device;

Fig. 2 shows in perspective the cathode structure of the electron discharge device;

Fig. 3 is an end view showing the radiator structure and Fig. 4 is a sectional view of the anode and radiator structure of the electron discharge device.

The electron discharge device illustrated is a high power rectifier having as electrodes a filamentary cathode and a cylindrical anode. The envelope has a tubular glass portion 1 with a reentrant stem 2 in which conductors 3 arev sealed at a pinch (not shown) within a shield 4. The shield is supported for rigidity upon a stub wire sealed in the pinch but is also electrically connected to one of the conductors 3. These conductors pass freely through apertures in the end cap 4a of the shield and support a filamentary cathode 5 which is arranged as shown in Figure 2.

The envelope is completed by a cylindrical anode 6 sealed at one end to the glass, portion I and closed at the other end. This anode 6 surrounds and co-operates with the, cathode 5.

The overall length of the embodiment shown is about 20 inches, the glass portion I being just less than 3 inches in diameter.

For the dissipation of heat by conduction to surrounding air, a radiator structure is mounted on the anode 6. This structure comprises a plurality of sheet metal fins l disposed radially about the anode and maintained in close engagement with the anode by means of a metal ring or tube 8 at one end and a clamping device lfl, H, I2 at the other end.

The tube 8 has an inwardly projecting flange 8a (Fig. 4) which is slotted to receive the fins at spaced intervals. The fins are cut away to leave overhanging portions 1a which interlock with the flange 8a. The fins have projections 1b which enter a circumferential groove in the anode 6 to determine the axial position of the fins. The outer ends of the fins have inwardly projecting parts 'lc extending over the end face of the anode and the spacing of these parts is determined by a disc 9 lying upon the end face of the anode and having a slotted upwardly projecting flange 9a. The clamping device comprises an internally coned collar In which is forced over projections hi on the fins by rotating a screw II in a nut l2, the nut being held in slots in the fins as shown in Fig. 4. The extremities of the inwardly-projecting portions of the fins are chamfered as necessary to allow them to be drawn together by the clamping device.

Various modifications will be readily apparent without departing from the idea of utilising a number of separate fins so shaped that they are interlocking in conjunction with other piece parts of suitable simple shapes, the whole being rigidly held together by means of a single locking element, such as a screw, an adjustable band or a spring.

The advantage of such an arrangement is that cast parts are eliminated, thus simplifying production, while at the same time the rigidity of cast parts is achieved by other means. A further advantage is that better thermal contact is secured. This is because the number of separate pieces is much greater than with cast parts, and while it is possible to secure at least three points of contact between any two solid objects by suitably shaping one of them, yet it is not possible to be sure of more than three points of 3 contact. Thus with a radiator consisting of many separate partsjone can be sure of more points of contact between the radiator and the hot body than is possible with a radiator consisting of a few parts only. Such a built-up radiator can also be made lighter than one made up from cast parts, as only the minimum quantityoi ma-, terial necessary need be used, Whereas with cast parts casting requirements impose minimum limits on the thickness of materials.

What is claimed is:

1. Heat radiating structure comprising a plurality of separate fins disposed radially about a cylindrical shell of electrical apparatus from which heat is to be dissipated, a ring surrounding and. engaging the fins at one end thereof; said ring being preferably internally slotted to space said fins, and a clamping member at the other end comprising a second ring axially movable, over a portion of each fin, said portion of each 'fin being radially tapered, said second ring having a coned inner surface engageable with said fintportions to urge said fins into close contact with the shell.

2. Heat radiating structure according to claim .1 wherein the clamped ends=of thefinspass over an end face of :the shell and are bunched closely together at the clamp.

3. Heat radiating structure according to claim 1 wherein said electrical apparatus comprises an electron discharge device, an anode which is part of the envelop of said device constituting said -;shell.- 1 I REGINALD ALEXANDER LISTER COLE.

RfifiERENCES CITED n follgwing references are of record in the file of this patent:

Austria Aug.20, 1942 

